US20150267101A1 - Coolant having rapid metal passivation properties - Google Patents

Coolant having rapid metal passivation properties Download PDF

Info

Publication number
US20150267101A1
US20150267101A1 US14/731,132 US201514731132A US2015267101A1 US 20150267101 A1 US20150267101 A1 US 20150267101A1 US 201514731132 A US201514731132 A US 201514731132A US 2015267101 A1 US2015267101 A1 US 2015267101A1
Authority
US
United States
Prior art keywords
group
solution
hydrogen
phosphonate
nitrite
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US14/731,132
Other versions
US10246622B2 (en
Inventor
Sandra G. Claeys
Serge S. Lievens
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Arteco NV
Original Assignee
Chevron USA Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chevron USA Inc filed Critical Chevron USA Inc
Priority to US14/731,132 priority Critical patent/US10246622B2/en
Publication of US20150267101A1 publication Critical patent/US20150267101A1/en
Assigned to CHEVRON U.S.A. INC. reassignment CHEVRON U.S.A. INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CLAEYS, SANDRA G., LIEVENS, SERGE S.
Assigned to ARTECO NV reassignment ARTECO NV NUNC PRO TUNC ASSIGNMENT (SEE DOCUMENT FOR DETAILS). Assignors: CHEVRON U.S.A. INC
Application granted granted Critical
Publication of US10246622B2 publication Critical patent/US10246622B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K5/00Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
    • C09K5/08Materials not undergoing a change of physical state when used
    • C09K5/10Liquid materials
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K5/00Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
    • C09K5/20Antifreeze additives therefor, e.g. for radiator liquids
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/05Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
    • C23C22/60Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using alkaline aqueous solutions with pH greater than 8
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/05Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
    • C23C22/60Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using alkaline aqueous solutions with pH greater than 8
    • C23C22/66Treatment of aluminium or alloys based thereon
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23FNON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/08Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
    • C23F11/18Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
    • C23F11/181Nitrogen containing compounds
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23FNON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/08Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
    • C23F11/18Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
    • C23F11/184Phosphorous, arsenic, antimony or bismuth containing compounds
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23FNON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/08Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
    • C23F11/18Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
    • C23F11/187Mixtures of inorganic inhibitors
    • C23F11/188Mixtures of inorganic inhibitors containing phosphates

Definitions

  • This invention is directed to nitrite containing coolant formulations that provide long lasting corrosion protection for the surfaces of lightweight metals used in modern cooling system designs.
  • Coolants heat transfer solutions
  • Coolants are used to remove heat from engines, particularly in combustion engines of the automotive industry.
  • excess heat should be removed as quickly as possible without damaging or decreasing the operation of all cooling system parts.
  • Much progress has been made towards the protection of the cooling system materials especially in the area of protection (passivation) against corrosion at high temperatures.
  • temperatures close to boiling are indeed very critical, the low temperature domain is also of high importance during engine operation. At temperature below the freezing point, not the corrosion protection but the solubility and low temperature pumpability is of major importance.
  • the coolant remains transparent and free of insoluble materials. Haziness, precipitation, or in extremes, gel formation are considered detrimental for the performance of an engine coolant. Deposit formation, on the one hand, will result in abrasive conditions and will physical damage soft materials in the cooling system. Problems resulting from instability can be seen in water pump seals, engine head seals, hoses or any other parts where softer materials are in use. Gel formation, on the other hand will have a negative impact on the viscosity and results in a negative change of the heat transfer characteristics of the fluid and can be observed in the heat exchangers of the cooling system.
  • a coolant formulation contains nitrite in the ranges set forth as follows, it is acceptable for wet liner cavitation protection to Original Equipment Manufacturers. This is based on the historically positive observations and conclusions that nitrite has shown over decades of its capability of providing ferrous alloys protection from cavitation damage.
  • Group III metals such as aluminum and its alloys are used as an alternative to other metals such as cast iron, copper, solder, brass, steel, magnesium, and their alloys in the construction of different components.
  • Modern heat exchangers and water pumps are the best known examples of such components.
  • aluminum due to its lower weight combined with acceptable strength and efficient heat transfer properties.
  • an additive package containing corrosion inhibitors is generally added to the coolant base fluid.
  • Various corrosion inhibitors have been added to water/alcohol based coolants and heat transfer fluids to reduce corrosion of metallic systems.
  • Carboxylate corrosion inhibitor combinations are well known, e.g. non-silicate antifreeze formulations containing alkali metal salts of benzoic acid, dicarboxylic acids and nitrate.
  • corrosion inhibitors comprising the combination of an aliphatic monoacid or salt, a hydrocarbyl dibasic acid or salt and a hydrocarbyl triazole are also known.
  • a corrosion inhibitor using an alkylbenzoic acid salt, an aliphatic monoacid or salt and a hydrocarbyl triazole has also been disclosed, as have phosphate and nitrite free antifreeze formulations containing aliphatic monobasic acids or salts, an alkali metal borate compound and a hydrocarbyl triazole.
  • Antifreeze compositions containing an aliphatic monoacid or salt, a hydrocarbonyl triazol and imidazol have also been described.
  • nitrite containing coolants are still widely used, certainly in the U.S. market, a need is present for nitrite containing coolant formulations that also provide long lasting corrosion protection for the increased aluminum surfaces in modern cooling system designs.
  • Coolant formulations comprising following additives allow for a fast passivation of the metal despite the presence of nitrites Ammonia formation and corresponding increase of pH is suppressed:
  • Compounds providing fast passivation include: phosphonates with formula R-[CR 2 ] m -PO 3 M 2 wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino or R is part of an aryl group.
  • the other R groups may be the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phophono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion.
  • Additional compounds include: phosphinates with formula R-[CR 2 ] m P(O 2 M)H (wherein at least one R-group is a hydrogen, alkyl alkenyl, hydroxyl, phosphino group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion.
  • This invention is directed to a heat transfer solution which results in rapid passivation when placed in contact with metal surfaces such as aluminum, and the process of passivating such metals with the solution.
  • This solution is composed of a fluid comprising water, alcohol or a mixture of both.
  • This solution further comprises nitrites, at least 1% of an organic corrosion inhibitor organic salt thereof, and at least one component selected out of groups of phosphonates and phosphinates.
  • the water-soluble liquid alcohols useful in this invention may comprise monohydroxy lower alkyl alcohols and liquid polyhydroxy alcohols such as the alkylene and dialkylene glycols. They may also comprise alkylene glycols, glycol monoethers, glycerins and mixtures thereof. Specific examples of the alcohol contemplated herein are methanol, ethanol, propanol, isopropanol, butanol, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol and mixtures thereof.
  • a preferred glycol is ethylene glycol, which as sold commercially often contains a small amount, up to 5% by weight, of diethylene glycol.
  • ethylene glycol as used herein is intended to include either the pure or commercial compound. This is also true of the other freezing point depressant alcohols contemplated herein.
  • the phosphonates have the formula R-[CR 2 ]m-PO 3 M 2 (wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may be the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phophono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion.
  • the phosphinates have the formula R-[CR 2 ]m-P(O 2 M)H (wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion combinations of two or more of these phosphonates and/or phosphinates.
  • the heat transfer fluids described above can further comprise one or more alkaline earth metal (Group II of the periodic table of elements) compounds such as magnesium and/or strontium.
  • alkaline earth metal Group II of the periodic table of elements
  • the heat transfer fluid described above can further comprise corrosion inhibitors selected from the group consisting of silicates, molybdates, nitrates, azoles and a combination of the foregoing compounds.
  • CAB controlled atmosphere brazed
  • Aluminum radiator cube material is immersed in 275 ml of a 50/50 coolant dilution (50% water and 50% coolant concentrate) in deionized water in a closed flask at 100° C. for 10 days. After the test, the nitrite concentration in the coolant is determined, together with the change in pH.
  • an antifreeze composition comprising from 50 to 99.8 wt. % of a glycol-based freezing point depressant selected from the group of: alkylene glycols, glycol monoethers, glycerins, and mixtures thereof 0.01 to 1 wt. % of sodium nitrite. From 0.0001 to 1% of a phosphonate with formula R-[CR 2 ] m -PO 3 M 2 and from 1 to 5% of an organic corrosion inhibitor or a salt thereof.
  • an antifreeze composition comprising from 50 to 99.8 wt % of a glycol-based freezing point depressant selected from the group of: alkylene glycols, glycol monoethers, glycerins and mixtures thereof; 0.01 to 1 wt % of sodium nitrite. From 0.0001 to 1% of a phosphonate with formula R-[CR 2 ] m -PO 3 M 2 . From 0.0001 to 0.1 wt % of alkaline earth metal (Group II of the periodic table of elements) compounds and from 1 to 5% of an organic corrosion inhibitor or a salt thereof.
  • a glycol-based freezing point depressant selected from the group of: alkylene glycols, glycol monoethers, glycerins and mixtures thereof; 0.01 to 1 wt % of sodium nitrite. From 0.0001 to 1% of a phosphonate with formula R-[CR 2 ] m -PO 3 M 2 . From 0.0001 to 0.1
  • an antifreeze composition as described in previous embodiments but in which the phosphonates are replaced with 0.0001 to 1% of a phosphinate with formula R-[CR 2 ]m-P(O 2 M)H.
  • Comparative examples 1-3 of the Table illustrate the potential negative effect of nitrites in coolants (nitrite depletion and pH increase) without the extra addition of additives described in the claims of this invention. Comparison of Comparative Examples 1-3 with Examples 1-6 demonstrates that with the addition of strontium nitrate, pH change and nitrite depletion is even further reduced.
  • coolant additives comprising but not limited to the group of silicates, molybdates, nitrates, azoles, pH buffers, hard water stabilizers, antifoam agents, colorants.
  • the composition is used as a concentrate in a mixture with an aqueous antifreeze solution comprising 10 to 90 wt. % by weight of water.

Abstract

It has been found that the chemical reactivity of the metal surface of heat exchangers with coolants in presence of nitrites can be reduced by the addition of additives such as phosphonates or phosphinates. Aluminum, other Group III metals, as well as other metals commonly used in cooling systems, such as those of automobile engines, may thus be effectively protected.

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • This application is a continuation of U.S. application Ser. No. 13/603,789 filed Sep. 5, 2012, entitled “Coolant Having Rapid Metal Passivation Properties”, the contents of which are incorporated herein by reference in their entirety.
  • FIELD OF THE INVENTION
  • This invention is directed to nitrite containing coolant formulations that provide long lasting corrosion protection for the surfaces of lightweight metals used in modern cooling system designs.
  • BACKGROUND OF THE INVENTION
  • Coolants (heat transfer solutions) are used to remove heat from engines, particularly in combustion engines of the automotive industry. In order to provide optimal efficiency to the engine, excess heat should be removed as quickly as possible without damaging or decreasing the operation of all cooling system parts. Much progress has been made towards the protection of the cooling system materials especially in the area of protection (passivation) against corrosion at high temperatures. Although, from a corrosion standpoint temperatures close to boiling are indeed very critical, the low temperature domain is also of high importance during engine operation. At temperature below the freezing point, not the corrosion protection but the solubility and low temperature pumpability is of major importance.
  • Ideally the coolant remains transparent and free of insoluble materials. Haziness, precipitation, or in extremes, gel formation are considered detrimental for the performance of an engine coolant. Deposit formation, on the one hand, will result in abrasive conditions and will physical damage soft materials in the cooling system. Problems resulting from instability can be seen in water pump seals, engine head seals, hoses or any other parts where softer materials are in use. Gel formation, on the other hand will have a negative impact on the viscosity and results in a negative change of the heat transfer characteristics of the fluid and can be observed in the heat exchangers of the cooling system.
  • In both heavy duty and off highway applications, the use of nitrite alone and in the combination with molybdate is still widespread for the protection of an engine's ferrous wet sleeve liner from cavitation. The use of such coolant formulations containing nitrite is widely spread in the United States, since many fleet and truck owners as well as the Truck Maintenance Council (TMC) have published recommended practice guidelines. TMC publishes the Recommended Practices Manual. This comprehensive manual contains more than 250 Recommended Practices (RPs). A Recommended Practice is a specification or practice, the adoption of which is voluntary. It is used to assist fleets and equipment manufacturers in the purchase, design, maintenance and performance of their equipment. TMC issues two types of RPs: Recommended Maintenance Practices, and Recommended Engineering Practices, Recommended Maintenance Practices are voluntary practices that assist equipment users, vehicle/component manufacturers, and other industry suppliers in the maintenance of commercial vehicle equipment. They also include informational documents that cover technical aspects of maintenance, equipment and supporting technologies. Recommended Engineering Practices are voluntary practices that assist equipment users, vehicle/ component manufacturers, and other industry suppliers in the design, specification, construction and performance of commercial vehicle equipment.
  • Until a clear and differentiating test method exists that can provide guarantee for the protection against cavitation, a coolant which contains nitrite remains recommended to guarantee sufficient protection of the liners. The applicable recommended practice guideline is RP329, Fleet Purchasing Specification for Nitrite-Containing Ethylene Glycol Base Coolant. This Recommended Practice specifies requirements for concentrated and prediluted forms of fully-formulated ethylene glycol base antifreeze/coolant which does not require a precharge of supplemental coolant additives.
  • If a coolant formulation contains nitrite in the ranges set forth as follows, it is acceptable for wet liner cavitation protection to Original Equipment Manufacturers. This is based on the historically positive observations and conclusions that nitrite has shown over decades of its capability of providing ferrous alloys protection from cavitation damage.
      • Concentrated antifreeze w/coolant must contain either : A. at least 2400 ppm nitrite (as NO2 ); or B. a combined total of at least 1560 ppm nitrite(as NO2 ) plus molybdate (as MoO4 2 ) ; with a minimum of 600 ppm of either.
      • Prediluted antifreeze/coolant must contain either: A. at least 1200 ppm nitrite (as NO2 ) or B. a combined total of at least 780 ppm nitrite(as NO2 ) plus molybdate (as MoO4 2 ); with a minimum of 300 ppm of either.
  • In today's engine applications, large amounts of lightweight , Group III metals such as aluminum and its alloys are used as an alternative to other metals such as cast iron, copper, solder, brass, steel, magnesium, and their alloys in the construction of different components. Modern heat exchangers and water pumps are the best known examples of such components. There is particular interest in aluminum due to its lower weight combined with acceptable strength and efficient heat transfer properties.
  • In order to protect the cooling system and engine parts against corrosion, an additive package containing corrosion inhibitors is generally added to the coolant base fluid. Various corrosion inhibitors have been added to water/alcohol based coolants and heat transfer fluids to reduce corrosion of metallic systems. Carboxylate corrosion inhibitor combinations are well known, e.g. non-silicate antifreeze formulations containing alkali metal salts of benzoic acid, dicarboxylic acids and nitrate. Alternately, corrosion inhibitors comprising the combination of an aliphatic monoacid or salt, a hydrocarbyl dibasic acid or salt and a hydrocarbyl triazole are also known. A corrosion inhibitor using an alkylbenzoic acid salt, an aliphatic monoacid or salt and a hydrocarbyl triazole has also been disclosed, as have phosphate and nitrite free antifreeze formulations containing aliphatic monobasic acids or salts, an alkali metal borate compound and a hydrocarbyl triazole. Antifreeze compositions containing an aliphatic monoacid or salt, a hydrocarbonyl triazol and imidazol have also been described.
  • The addition of phosphonocarboxylates to coolants as a corrosion inhibitor in combination with inorganic phosphates, is known, combinations of phosphonocarboxylates and strontium or magnesium or calcium compounds were explored but are limited to the use of phosphonate 2-phosphonobutane-1,2,4-tricarboxylic acid or a salt thereof.
  • Recently, fast depletion of certain corrosion inhibitors such as nitrites, and silicates, has been observed in the field, together with an important pH increase. Those changes to the coolant can have a negative effect on its stability and long term performance. Test work conducted has indicated that these coolant changes occur in different type of heat exchangers, with both brazed and unbrazed surfaces. The changes observed in the coolant can be explained by the known chemical reaction of nitrites with unpassivated metals, such as aluminum, in the presence of sodium hydroxide. This results in the formation of ammonia and aluminum oxides and with a pH increase as result.
  • Earlier studies have indicated that reduction of nitrites and pH increase in the coolant could be inhibited by pre-washing the brazed surfaces of metals such as aluminum with a phosphate solution, neutral to slight alkaline, prior to contact with the coolant.
  • Because nitrite containing coolants are still widely used, certainly in the U.S. market, a need is present for nitrite containing coolant formulations that also provide long lasting corrosion protection for the increased aluminum surfaces in modern cooling system designs.
  • SUMMARY OF THE INVENTION
  • It has been found that the chemical reactivity of the metal surface with coolants in presence of nitrites and without inorganic phosphates can be reduced by addition of certain additives. Coolant formulations comprising following additives allow for a fast passivation of the metal despite the presence of nitrites Ammonia formation and corresponding increase of pH is suppressed:
  • Compounds providing fast passivation include: phosphonates with formula R-[CR2]m-PO3M2 wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino or R is part of an aryl group. The other R groups may be the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phophono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion.
  • Additional compounds include: phosphinates with formula R-[CR2]mP(O2M)H (wherein at least one R-group is a hydrogen, alkyl alkenyl, hydroxyl, phosphino group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion.
  • It has also been found that phosphonocarboxylates in nitrite containing coolants are much less effective in suppressing the nitrite depletion reaction and the resulting pH increase in comparison with the phosphonate technologies described in this invention.
  • DETAILED DESCRIPTION OF THE INVENTION
  • This invention is directed to a heat transfer solution which results in rapid passivation when placed in contact with metal surfaces such as aluminum, and the process of passivating such metals with the solution. This solution is composed of a fluid comprising water, alcohol or a mixture of both. This solution further comprises nitrites, at least 1% of an organic corrosion inhibitor organic salt thereof, and at least one component selected out of groups of phosphonates and phosphinates.
  • The water-soluble liquid alcohols useful in this invention may comprise monohydroxy lower alkyl alcohols and liquid polyhydroxy alcohols such as the alkylene and dialkylene glycols. They may also comprise alkylene glycols, glycol monoethers, glycerins and mixtures thereof. Specific examples of the alcohol contemplated herein are methanol, ethanol, propanol, isopropanol, butanol, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol and mixtures thereof. A preferred glycol is ethylene glycol, which as sold commercially often contains a small amount, up to 5% by weight, of diethylene glycol. The term ethylene glycol as used herein is intended to include either the pure or commercial compound. This is also true of the other freezing point depressant alcohols contemplated herein.
  • The phosphonates have the formula R-[CR2]m-PO3M2 (wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may be the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phophono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion.
  • The phosphinates have the formula R-[CR2]m-P(O2M)H (wherein at least one R-group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, CO, amino, alkylamino or R is part of an aryl group, the other R groups may the same as or different from the first R group is a hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, CO, amino, alkylamino, m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion combinations of two or more of these phosphonates and/or phosphinates.
  • The heat transfer fluids described above can further comprise one or more alkaline earth metal (Group II of the periodic table of elements) compounds such as magnesium and/or strontium.
  • The heat transfer fluid described above can further comprise corrosion inhibitors selected from the group consisting of silicates, molybdates, nitrates, azoles and a combination of the foregoing compounds.
  • EXAMPLES
  • The positive effect towards fast passivation and reduced nitrite consumption has been illustrated on controlled atmosphere brazed (CAB) aluminum heat exchanger material immersed in a cooling fluid.
  • Description of the Test
  • Aluminum radiator cube material is immersed in 275 ml of a 50/50 coolant dilution (50% water and 50% coolant concentrate) in deionized water in a closed flask at 100° C. for 10 days. After the test, the nitrite concentration in the coolant is determined, together with the change in pH.
  • One can observe that multiple additives can provide a positive effect on pH stability or stability of the nitrite concentration but the solution of this invention gives very good results for both characteristics. Moreover, it can be observed that the selection of the correct phosphonate or phosphinate, respectively is critical to obtain a good performance level. The use of other phosphonates like the ones put forward in the prior art literature (e.g. phosphonocarboxylates as described in patent application US2010116473) does not give the targeted stability of pH, nor does it stop the consumption of nitrite.
  • In one embodiment, there is provided an antifreeze composition comprising from 50 to 99.8 wt. % of a glycol-based freezing point depressant selected from the group of: alkylene glycols, glycol monoethers, glycerins, and mixtures thereof 0.01 to 1 wt. % of sodium nitrite. From 0.0001 to 1% of a phosphonate with formula R-[CR2]m-PO3M2 and from 1 to 5% of an organic corrosion inhibitor or a salt thereof.
  • In a second embodiment, there is provided an antifreeze composition comprising from 50 to 99.8 wt % of a glycol-based freezing point depressant selected from the group of: alkylene glycols, glycol monoethers, glycerins and mixtures thereof; 0.01 to 1 wt % of sodium nitrite. From 0.0001 to 1% of a phosphonate with formula R-[CR2]m-PO3M2. From 0.0001 to 0.1 wt % of alkaline earth metal (Group II of the periodic table of elements) compounds and from 1 to 5% of an organic corrosion inhibitor or a salt thereof.
  • In a third embodiment there is provided an antifreeze composition as described in previous embodiments but in which the phosphonates are replaced with 0.0001 to 1% of a phosphinate with formula R-[CR2]m-P(O2M)H.
  • Examples of the described embodiments are given in the attached table (Ex. 1-6).
  • Comp. Comp. Comp.
    Component Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 1 Ex. 2 Ex. 3
    mono ethylene glycol 94.0855 94.0255 94.1209 94.0609 94.1232 94.0632 94.0009 94.1430 94.1130 94.0930
    2-ethylhexanoic acid 3.2400 3.2400 3.2400 3.2400 3.2400 3.2400 3.2400 3.2400 3.2400 3.2400
    Sebacic acid 0.2520 0.2520 0.2520 0.2520 0.2520 0.2520 0.2520 0.2520 0.2520 0.2520
    Tolyltriazole 0.2000 0.2000 0.2000 0.2000 0.2000 0.2000 0.2000 0.2000 0.2000 0.2000
    NaOH1 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000
    NaNO2 0.1650 0.1650 0.1650 0.1650 0.1650 0.1650 0.1650 0.1650 0.1650 0.1650
    Sr(NO3)2 0.0600 0.0600 0.0600 0.0600 0.0300
    Dequest 20102 0.0575 0.0575
    Phenylphosphonic acid 0.0221 0.0221 0.0221
    Phenylphosphinic acid 0.0198 0.0198
    Dequest 70003 0.0500
    Sodium molybdate 0.0600
    dihydrate
    pH before test 8.6 8.7 8.6 8.6 8.6 8.6 8.6 8.5 8.5 8.5
    pH after test 8.8 8.8 8.9 8.8 9.0 8.8 8.7 9.3 9.1 9.2
    pH change 0.2 0.1 0.3 0.2 0.4 0.2 0.1 0.8 0.6 0.7
    NO2 (%)4 6 4 18 14 23 15 11 39 39 39
    1NaOH: 50 wt % aqueous solution of sodium hydroxide
    2Dequest 2010: 60 wt % 1-Hydroxyethylidene -1,1,-diphosphonic acid aqueous solution, commercially available at Thermphos
    3Dequest 7000: 50 wt % of 2-phosphonobutane-1,2,4-tricarboxylic acid aqueous solution, commercially available at Thermphos
    4% percentage of nitrites depleted after test
  • Comparative examples 1-3 of the Table illustrate the potential negative effect of nitrites in coolants (nitrite depletion and pH increase) without the extra addition of additives described in the claims of this invention. Comparison of Comparative Examples 1-3 with Examples 1-6 demonstrates that with the addition of strontium nitrate, pH change and nitrite depletion is even further reduced.
  • Additionally to above critical additives also other typical coolant additives can be added comprising but not limited to the group of silicates, molybdates, nitrates, azoles, pH buffers, hard water stabilizers, antifoam agents, colorants.
  • In one embodiment, the composition is used as a concentrate in a mixture with an aqueous antifreeze solution comprising 10 to 90 wt. % by weight of water.

Claims (23)

What is claimed is:
1. A heat transfer solution which provides passivation when placed in contact with metal surfaces, said solution comprising:
(a) water, an alcohol, or a mixture of both;
(b) a nitrite; and
(c) a phosphonate having the formula R-[CR2]m-PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion, or phosphinate having the formula R-[CR2]m-P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion.
2. The solution of claim 1, wherein the alcohol is water soluble.
3. The solution of claim 2, wherein the water soluble alcohol is selected from the group consisting of methanol, ethanol, propanol, ispropanol, butanol, glycols, glycol monoethers, glycerins and mixtures thereof.
4. The solution of claim 3, wherein the glycol is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, butylene glycol and mixtures thereof
5. The solution of claim 4, wherein the glycol is ethylene glycol.
6. The solution of claim 1, wherein the solution further comprises a corrosion inhibitor salt which is selected from the group consisting of silicates, molybdates, nitrates, azoles and combinations thereof.
7. The solution of claim 1, wherein the heat transfer solution further comprises an alkaline earth metal compound.
8. The solution of claim 1, which further comprises from 50 to 99.8 wt % of the liquid of (a).
9. The solution of claim 1, which comprises from 0.01 to 1 wt % of the nitrite of (b).
10. The solution of claim 1, wherein the nitrite is sodium nitrite.
11. The solution of claim 1, which comprises from 0.0001 to 1 wt % of the phosphonate or phosphinate of (c).
12. The solution of claim 1 which further comprises additives selected from the group consisting of pH buffers, hard water stabilizers, antifoam agents, and colorants.
13. A process for passivation of metal surfaces, wherein the surfaces are treated with a solution comprising: (a) a liquid selected from the group consisting of water, an alcohol, and a mixture of both; (b) a nitrite and (c) a phosphonate having the formula R-[CR2]m-PO3M2 wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphono group, carbonyl group, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and each M is hydrogen or an alkali metal ion, or phosphinate having the formula R-[CR2]m-P(O2M)H wherein each R-group is selected from the group consisting of hydrogen, alkyl, alkenyl, hydroxyl, phosphino group, carbonyl compound, amino, alkylamino and an aryl group, wherein m is 1 or an integer greater than 1, and M is hydrogen or an alkali metal ion.
14. The process of claim 13, wherein the solution further comprises a corrosion inhibitor salt.
15. The process of claim 14, wherein the corrosion inhibitor salt is selected from the group consisting of silicates, molybdates, nitrates, azoles and combustions thereof
16. The process of claim 13, wherein the solution further comprises an alkaline earth metal compound.
17. The process of claim 16, wherein the alkaline earth metal compound comprises strontium nitrate and (c) is a phosphonate and comprises 1-hydroxyethylidene-1, 1-diphosphonic acid or phenylphosphonic acid.
18. The solution of claim 7, wherein the alkaline earth metal compound is a strontium or magnesium compound.
19. The solution of claim 7, wherein the alkaline earth metal compound comprises strontium nitrate and (c) is a phosphonate which comprises 1-hydroxyethylidene-1, 1-diphosphonic acid or phenylphosphonic acid.
20. The solution of claim 1, wherein the solution further comprises an organic corrosion inhibitor salt.
21. The solution of claim 13, wherein the solution further comprises an organic corrosion inhibitor salt.
22. The process of claim 13, wherein (c) is a phosphonate and comprises 1-hydroxyethylidene-1, 1-diphosphonic acid or phenylphosphonic acid.
23. The solution of claim 1, wherein (c) is a phosphonate and comprises 1-hydroxyethylidene-1, 1-diphosphonic acid or phenylphosphonic acid.
US14/731,132 2012-09-05 2015-06-04 Coolant having rapid metal passivation properties Active US10246622B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/731,132 US10246622B2 (en) 2012-09-05 2015-06-04 Coolant having rapid metal passivation properties

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/603,789 US9115302B2 (en) 2012-09-05 2012-09-05 Coolant having rapid metal passivation properties
US14/731,132 US10246622B2 (en) 2012-09-05 2015-06-04 Coolant having rapid metal passivation properties

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US13/603,789 Continuation US9115302B2 (en) 2012-09-05 2012-09-05 Coolant having rapid metal passivation properties

Publications (2)

Publication Number Publication Date
US20150267101A1 true US20150267101A1 (en) 2015-09-24
US10246622B2 US10246622B2 (en) 2019-04-02

Family

ID=50186145

Family Applications (2)

Application Number Title Priority Date Filing Date
US13/603,789 Active 2033-03-05 US9115302B2 (en) 2012-09-05 2012-09-05 Coolant having rapid metal passivation properties
US14/731,132 Active US10246622B2 (en) 2012-09-05 2015-06-04 Coolant having rapid metal passivation properties

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US13/603,789 Active 2033-03-05 US9115302B2 (en) 2012-09-05 2012-09-05 Coolant having rapid metal passivation properties

Country Status (1)

Country Link
US (2) US9115302B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018013630A1 (en) 2016-07-12 2018-01-18 Prestone Products Corporation Heat transfer fluids and methods for preventing corrosion in heat transfer systems
CN107987803A (en) * 2016-10-26 2018-05-04 中国石油化工股份有限公司 A kind of phosphorous engine coolant and preparation method thereof

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9332673B2 (en) * 2013-10-17 2016-05-03 Globalfoundries Inc. Surface modification of hoses to reduce depletion of corrosion inhibitor
CN112500837A (en) * 2020-12-28 2021-03-16 张敬宣 Novel heating liquid preparation process and use method
WO2023180531A1 (en) 2022-03-25 2023-09-28 Arteco N.v. Heat-transfer fluid with low electrical conductivity

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4414126A (en) * 1981-10-22 1983-11-08 Basf Wyandotte Corporation Aqueous compositions containing corrosion inhibitors for high lead solder
US4557896A (en) * 1980-09-25 1985-12-10 Dearborn Chemicals Limited Treatment of aqueous systems
US4626367A (en) * 1983-06-10 1986-12-02 Kao Corporation Water-soluble metal-working lubricant composition
US5076951A (en) * 1989-05-19 1991-12-31 Ciba-Geigy Corporation Antifreeze compositions
US5718836A (en) * 1994-05-12 1998-02-17 Japan Chemical Industries Co., Ltd. Liquid coolant compositions with anti-corrosive property containing magnesium and calcium compounds
US6228283B1 (en) * 1998-05-22 2001-05-08 Ashland Inc. Aqueous corrosion inhibitor
US6508951B1 (en) * 1999-09-02 2003-01-21 Cci Kabushiki Kaisha Low P type coolant composition
US7258814B2 (en) * 2003-10-01 2007-08-21 Shishiai-Kabushikigaisha Coolant composition and methods of use thereof

Family Cites Families (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3699052A (en) * 1969-11-12 1972-10-17 Drew Chem Corp Corrosion inhibitor composition containing a glycine,chelating agent,phosphoric or boric acid ester,and a water soluble divalent metal salt
US4452715A (en) * 1982-10-25 1984-06-05 Basf Wyandotte Corporation High pH coolant containing carbonate ion
AU572825B2 (en) * 1983-03-03 1988-05-19 Fmc Corporation (Uk) Limited Inhibition of corrosion and scale formation of metal surfaces
US4587028A (en) 1984-10-15 1986-05-06 Texaco Inc. Non-silicate antifreeze formulations
US4647392A (en) 1985-12-27 1987-03-03 Texaco Inc. Monobasic-dibasic acid/salt antifreeze corrosion inhibitor
US4759864A (en) 1987-09-04 1988-07-26 Texaco Inc. & S.A. Texaco Petro, N.V. Corrosion-inhibited antifreeze formulation
US4851151A (en) 1988-05-06 1989-07-25 Texaco Inc. Process for production of synthesis gas with reduced sulfur content
DE4204809A1 (en) 1992-02-18 1993-08-19 Basf Ag HARDWATER-STABLE, PHOSPHATE-CONTAINING REFRIGERANT BLENDS
EP0564721B1 (en) 1992-04-06 1997-06-04 Texaco Services (Europe) Ltd. Corrosion-inhibiting antifreeze formulations
DE69828205T2 (en) 1998-05-06 2005-12-15 Shishiai-K.K., Seki DILUTED COOLANT
US6676847B2 (en) * 2000-02-25 2004-01-13 Ashland Inc. Monocarboxylic acid based antifreeze composition for diesel engines
US6878309B2 (en) * 2001-02-12 2005-04-12 Dober Chemical Corp. Controlled release cooling additive composition
JP2002294227A (en) 2001-03-29 2002-10-09 Komatsu Ltd Antifreeze/coolant composition
JP4224561B2 (en) 2003-09-22 2009-02-18 村▲瀬▼ 清隆 Coolant auxiliary liquid and method of using the same
CN1860199B (en) 2003-10-16 2010-06-09 Cci株式会社 Cooling agent composition
EP1688472A4 (en) 2003-11-26 2010-07-07 Shishiai Kk Cooling fluid composition
AU2003284506A1 (en) 2003-12-01 2005-06-24 Shishiai-Kabushikigaisha Coolant composition
JP2005187748A (en) 2003-12-26 2005-07-14 Cci Corp Cooling liquid composition
WO2007050568A2 (en) 2005-10-25 2007-05-03 Honeywell International Inc. Heat transfer fluid compositions for cooling systems containing magnesium or magnesium alloys
AU2008282497A1 (en) 2007-08-02 2009-02-05 Caterpillar Inc. Methods and compositions for passivating heat exchanger systems
US8617415B2 (en) 2008-11-07 2013-12-31 Prestone Products Corporation Heat transfer fluids and corrosion inhibitor formulations for use thereof
US8980815B2 (en) * 2011-02-25 2015-03-17 Prestone Products Corporation Composition for cleaning a heat transfer system having an aluminum component

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4557896A (en) * 1980-09-25 1985-12-10 Dearborn Chemicals Limited Treatment of aqueous systems
US4414126A (en) * 1981-10-22 1983-11-08 Basf Wyandotte Corporation Aqueous compositions containing corrosion inhibitors for high lead solder
US4626367A (en) * 1983-06-10 1986-12-02 Kao Corporation Water-soluble metal-working lubricant composition
US5076951A (en) * 1989-05-19 1991-12-31 Ciba-Geigy Corporation Antifreeze compositions
US5718836A (en) * 1994-05-12 1998-02-17 Japan Chemical Industries Co., Ltd. Liquid coolant compositions with anti-corrosive property containing magnesium and calcium compounds
US6228283B1 (en) * 1998-05-22 2001-05-08 Ashland Inc. Aqueous corrosion inhibitor
US6508951B1 (en) * 1999-09-02 2003-01-21 Cci Kabushiki Kaisha Low P type coolant composition
US7258814B2 (en) * 2003-10-01 2007-08-21 Shishiai-Kabushikigaisha Coolant composition and methods of use thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018013630A1 (en) 2016-07-12 2018-01-18 Prestone Products Corporation Heat transfer fluids and methods for preventing corrosion in heat transfer systems
CN107987803A (en) * 2016-10-26 2018-05-04 中国石油化工股份有限公司 A kind of phosphorous engine coolant and preparation method thereof

Also Published As

Publication number Publication date
US10246622B2 (en) 2019-04-02
US9115302B2 (en) 2015-08-25
US20140061529A1 (en) 2014-03-06

Similar Documents

Publication Publication Date Title
US10246622B2 (en) Coolant having rapid metal passivation properties
CA2520246C (en) Antifreeze concentrates and coolant compositions based on polyglycols and amides for protecting magnesium and the alloys thereof
JP2862007B2 (en) Corrosion inhibiting antifreeze composition
US8333904B2 (en) Antifreeze concentrates based on amides, and coolant compositions comprising them and intended for protecting magnesium and magnesium alloys
CA1258162A (en) Monobasic-dibasic acid/salt antifreeze corrosion inhibitor
EP0564721B1 (en) Corrosion-inhibiting antifreeze formulations
US20060033077A1 (en) Engine antifreeze composition
US6045719A (en) Use of quaternized imidazoles as corrosion inhibitors for non-ferrous metals, and coolant compositions and antifreeze concentrates comprising them
US5071582A (en) Coolant system cleaning solutions having silicate or siliconate-based corrosion inhibitors
JPH1067982A (en) Nonfreezing concentrate containing no silicate, borate and nitrate and readily applicable cooling composition containing the same
CA1249430A (en) Corrosion inhibiting functional fluid
JPH05306390A (en) Corrosion-inhibited antifreeze/coolant composition containing aromatic carboxylic acid
JPH06116764A (en) Antifreeze composition
JP2002523619A (en) Antifreeze compositions containing carboxylic and cyclohexenoic acid corrosion inhibitors
RU2249634C2 (en) Corrosion-inhibiting compositions for liquid heat carriers
CA2308195C (en) Silicate free antifreeze composition
JP2006052404A (en) Silicate-free cooling liquid having improved corrosiveness based on organic acid and carbamate
JPH04306291A (en) Antifreeze composition with controlled corrosiveness
US6235217B1 (en) Monocarboxylic acid based antifreeze composition
JPH0885782A (en) Antifreeze composition
CN114907820A (en) Extended service engine coolant composition
CZ20014588A3 (en) Corrosion-inhibiting composition for heat-carrying liquids
JPH10251624A (en) Antifreeze/coolant composition
MXPA01008616A (en) Monocarboxylic acid based antifreeze composition for diesel engines.
US6881355B2 (en) Antifreeze

Legal Events

Date Code Title Description
AS Assignment

Owner name: CHEVRON U.S.A. INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CLAEYS, SANDRA G.;LIEVENS, SERGE S.;REEL/FRAME:038924/0220

Effective date: 20160614

AS Assignment

Owner name: ARTECO NV, BELGIUM

Free format text: NUNC PRO TUNC ASSIGNMENT;ASSIGNOR:CHEVRON U.S.A. INC;REEL/FRAME:045739/0786

Effective date: 20171025

STCF Information on status: patent grant

Free format text: PATENTED CASE

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 4